irogers

5 ms·

1.
by irogers 2y ago
Just to advertise the perf tool has inbuilt flamegraph generation code these days (well leaning on D3.js). So `perf script report flamegraph` will convert a perf.data file into a flamegraph.html. Similarly there is `perf script report gecko
2.
by irogers 3y ago
Agreed this is awesome, obviously sanitizers fill some of this gap currently but they aren't great with things like reference counting that RAII makes a doddle. Fwiw, here is an implementation of a runtime RAII style checking on top of
3.
by irogers 3y ago
Somewhat related, "Data-type profiling for perf": https://lwn.net/Articles/955709/
4.
by irogers 3y ago
For a collection of profilers you can also check out the Profilerpedia: https://profilerpedia.markhansen.co.nz/
5.
by irogers 3y ago
There are also GC techniques to make the pause shorter, for example, doing the work for the pause concurrently and then repeating it in the safepoint. The hope is that the concurrent work will turn the safepoint work into a simpler check th
6.
by irogers 3y ago
This is awesome work and textual being able to support terminal or web ( https://github.com/Textualize/textual-web ) also gives hope that this can be more than a terminal app. I'm hoping that in the future features
7.
by irogers 4y ago
Wouldn't all your kernel stacks then end up in whatever this handler is? Why not implement your approach and mail it to LKML :-)
8.
by irogers 4y ago
prodfiler clearly has a market. It would be interesting to see the approach as something standard in the kernel tree, perhaps it can be added to perf's synthesis, etc. There is already BPF based profiling within perf to avoid file desc
9.
by irogers 4y ago
Allowing processes to sniff each others stacks has some fairly obvious security issues.
10.
by irogers 4y ago
For every running application turn DWARF data into BPF maps. Does this scale?
11.
by irogers 4y ago
AMD will have support in Zen4 and Linux 6.1 (which is LTS): https://lore.kernel.org/lkml/Yz%2FcpNTSacRMh1FK@gmail.com/ Further, precise events are fixed in Linux 6.2: https://lore.kernel.org/lkml&#
12.
by irogers 4y ago
DWARF bytecode is a full VM. Do compiler writers test their DWARF output? (my experience is not - especially for architectures out of the big 2 or 3) How does the kernel access the ELF file pages with the DWARF information in when in an NMI
13.
by irogers 4y ago
This could be a great Linux perf GSoC project. Projects and mentors are being looked for: https://wiki.linuxfoundation.org/gsoc/2023-gsoc-perf
14.
by irogers 4y ago
Agner speaks about memory renaming back on Zen 2: https://www.agner.org/forum/viewtopic.php?t=41 Intel Alderlake has performance events for tracking it: https://github.com/intel/perfmon/blob&#
15.
by irogers 4y ago
Twitter: "No need to recompile with frame pointers." Web page: "always-on profiling powered by eBPF technology." BPF stack traces are gathered using frame pointers: https://github.com/torvalds/linux&
16.
by irogers 4y ago
This seems relevant: Future of Memory Safety Challenges and Recommendations https://advocacy.consumerreports.org/wp-content/uploads/2023... """ Case Studies 1. The Python cryptographic authority is
17.
by irogers 4y ago
Problem with my open-source startup: https://docs.google.com/document/d/1kiW9qmNlJ9oQZM6r5o4_N54s... Worth a read and I'm sure Rui would appreciate ways to resolve this.
18.
by irogers 4y ago
People try to get cute with 3-way compares. A real Java bug that inspired: https://errorprone.info/bugpattern/BadComparable public MyFile implements Comparable { ... long timestamp; ... @Override public int compare
19.
by irogers 4y ago
Fwiw, this would fail Android's Compatibility Test Suite: https://android.googlesource.com/platform/cts/+/3ece5ae7a51d...
20.
by irogers 4y ago
Not having cognitive load motivates something like the LLAMA work: https://research.google/pubs/pub49008/
21.
by irogers 5y ago
The Linux Foundation also has projects in the Google Summer-of-Code (GSoC): https://wiki.linuxfoundation.org/gsoc/google-summer-code-202... In 2022 GSoC is expanding eligibility to non-students: https://open
22.
by irogers 5y ago
It can catch people by surprise that Java's narrowing conversions may not preserve the sign. For example, the following is broken: class TimestampedObject implements Comparable<TimestampedObject> { long timestamp; int compare
23.
by irogers 6y ago
String should be an interface/protocol. When I log a message, I want to pass a string. If I have to append large strings for a log message I don't want to run out of memory, I should be able to pass a rope/cord [1]. We'v
24.
by irogers 6y ago
Given there is before and after code, perhaps the translation can be automated. If the whole code base were auto-translated, what bugs could be detected and fed back to the C implementation? I'm assuming there is going to be hesitance
25.
by irogers 6y ago
The issue with BURS is that lookup tables can be 10s to 100s of MB. Most code generators will use dynamic programming, but hybrids have been considered: https://dl.acm.org/doi/10.1145/1133255.1133988 (Fast and fle